Internal carotid artery pseudoaneurysm is an uncommon complication of retropharyngeal and parapharyngeal abscess in children. Treatment of the pseudoaneurysm has evolved in recent years from surgical ligation to endovascular techniques. Neurologic sequelae most commonly consist of Horner's syndrome with cerebral ischemia being uncommon. The clinical course of a 2-year-old boy with retropharyngeal abscess complicated by internal carotid artery pseudoaneurysm, is described and the literature is reviewed. A conventional angiogram confirmed the presence of a large pseudoaneurysm with no anterograde flow distal to the pseudoaneurysm and substantial collateral flow across the circle of Willis, with filling of the left anterior and middle cerebral arteries via the anterior and posterior communicating arteries...

Stroke and related cerebrovascular diseases are a major cause of mortality and disability. Even at standard-field-strengths (1.5T), MRI is by far the most sensitive imaging technique to detect acute brain infarctions and to characterize incidental cerebrovascular lesions, such as white matter hyperintensities, lacunes and microbleeds. Arterial time-of-flight (TOF) MR angiography (MRA) can depict luminal narrowing or occlusion of the major brain feeding arteries, and this without the need for contrast administration...

OBJECTIVE The aim of this investigation was to modify the mini-pterional and mini-orbitozygomatic (mini-OZ) approaches in order to reduce the amount of tissue traumatization caused and to compare the use of the 2 approaches in the removal of circle of Willis aneurysms based on the authors' clinical experience and quantitative analysis. METHODS Three formalin-fixed adult cadaveric heads injected with colored silicone were examined. Surgical freedom and angle of attack of the mini-pterional and mini-OZ approaches were measured at 9 anatomical points, and the measurements were compared...

BACKGROUND AND PURPOSE: Intracranial atherosclerotic disease plaque hyperintensity and/or gadolinium contrast enhancement have been studied as imaging biomarkers of acutely symptomatic ischemic presentations using single static MR imaging measurements. However, the value in modeling the dynamics of intracranial plaque permeability has yet to be evaluated. The purpose of this study was to use dynamic contrast-enhanced MR imaging to quantify the contrast permeability of intracranial atherosclerotic disease plaques in symptomatic patients and to compare these parameters against existing markers of plaque volatility using black-blood MR imaging pulse sequences...

Moyamoya disease (MMD) is a rare neurovascular disorder which pathologically, is a chronic cerebrovasculopathy. It is characterized by stenosis of the internal carotid artery (ICA) and the main branches within the circle of Willis with consecutive development of collateral vessels. There are a few cases in the literature which have described movement disorders as a manifestation of MMD; however these have been uncommonly reported in cases of moyamoya syndrome (MMS). We present a 10-year-old boy with dystonia, myoclonus and encephalopathy like features...

Moyamoya disease is a rare chronic and progressive cerebrovascular disease of the arteries of the circle of Willis that can affect children and adults. It has been associated with multiple diseases, including immunologic, like Graves' disease, diabetes mellitus, and SLE. Hyperlipidemia has been recognized in patients with Moyamoya disease with an incidence of 27-37%. However, no case in pediatric patients has been reported of the coexistence of Moyamoya disease and hyperlipidemia. Here we present a case of a 9-year-old female diagnosed with Moyamoya disease after a stroke with incidental finding of familial hypercholesterolemia...

BACKGROUND AND PURPOSE: The presence of collaterals is associated with a reduced risk of stroke and transient ischemic attack in patients with steno-occlusive carotid artery disease. Although metabolic syndrome negatively impacts collateral status, it is unclear whether and to what extent type 2 diabetes mellitus affects cerebral collateral flow regulation during hypoperfusion. METHODS: We examined the spatial and temporal changes of the leptomeningeal collateral flow and the flow dynamics of the penetrating arterioles in the distal middle cerebral artery and anterior cerebral artery branches over 2 weeks after unilateral common carotid artery occlusion (CCAO) using optical coherent tomography in db/+ and db/db mice...

OBJECTIVE: Ischaemic stroke is a leading cause of death and disability. Autoregulation and collateral blood flow through the circle of Willis both play a role in preventing tissue infarction. To investigate the interaction of these mechanisms a one-dimensional steady state model of the cerebral arterial network was created. METHODS: Structural variants of the circle of Willis that present particular risk of stroke were recreated using a network model coupled with: (1) a steady state physiological model of cerebral autoregulation; (2) one wherein the cerebral vascular bed was modelled as a passive resistance...

Uniform international terminology is a fundamental issue of medicine. Names of various organs or structures have developed since early human history. The first proper anatomical books were written by Hippocrates, Aristotle and Galen. For this reason the modern terms originated from Latin or Greek. In a modern time the terminology was improved in particular by Vasalius, Fabricius and Harvey. Presently each known structure has internationally approved term that is explained in anatomical or histological terminology...

BACKGROUND: Congenital intracranial tumors as a group are quite rare, representing only 0.5% to 1.5% of all pediatric brain neoplasms. CASE REPORT: We reported a case of congenital mixed neuronal-glial tumor detected by ultrasound at 30 weeks of gestation. It showed that the tumor was 2.5 × 2.3 × 2.1 cm in size, located in the sellar region, regular shape, and slightly heterogeneous solid mass with a little cystic component. No color flow was present inside the tumor, but the peripheral encirclement by arterial circle of Willis...

BACKGROUND: Intracranial arterial calcification (ICAC) is frequently detected on head computed tomography and has been found to be associated with ischemic stroke by recent clinical studies. AIMS: Based on a hospital-based study, we aimed to compare the occurrence of cerebral microembolic signals (MES) among stroke patients with different degrees of ICAC, which may indicate the potential mechanisms linking ICAC and ischemic stroke in intracranial atherosclerosis patients...

The cerebral arterial circle (circulus arteriosus cerebri) or circle of Willis (CoW) is a circulatory anastomosis surrounding the optic chiasma and hypothalamus that supplies blood to the brain and surrounding structures. It has been implicated in several cerebrovascular disorders, including cerebral amyloid angiopathy (CAA)-associated vasculopathies, intracranial atherosclerosis and intracranial aneurysms. Studies of the molecular mechanisms underlying these diseases for the identification of novel drug targets for their prevention require animal models...

The progress in surgical treatment of intracranial aneurysms is based on the introduction of modern minimally invasive techniques. Among the variety of keyhole approaches, supraorbital craniotomy is most often used in surgical treatment of anterior circle of willis aneurysms. The authors present the preliminary results of application of supraorbital keyhole craniotomy for anterior circle of willis aneurysms in 27 patients. Most of the patients had unruptured aneurysms (18 patients). Nine patients had SAH, and 4 of them were operated on in the acute period...

AIM: To clarify the indications for surgical treatment and the principles for choosing a surgical technique for patients with unruptured asymptomatic aneurysms (UAAs) based on the results of direct and endovasal operations performed at the Burdenko Neurosurgical Institute and on the literature data. MATERIAL AND METHODS: The study included 694 UAA patients (481 females (69.3%) and 213 males (30.7%)) operated on at the Burdenko Neurosurgical Institute from 1997 to 2013...

The pathogenesis of subarachnoid hemorrhage remains unclear. No models of cerebral aneurysms elicited solely by surgical procedures and diet have been established. Elsewhere we reported that only few rats in our original rat aneurysm model manifested rupture at the anterior and posterior Willis circle and that many harbored unruptured aneurysms at the anterior cerebral artery-olfactory artery bifurcation. This suggests that rupture was site-specific. To test our hypothesis that a site-specific response to hemodynamic changes is associated with aneurysmal rupture, we modified our original aneurysm model by altering the hemodynamics...

BACKGROUND AND PURPOSE: Due to well-developed Circle of Willis in pigs, it is technically challenging to make persistent focal ischemic stroke based on occlusion of cerebral arteries. Endothelin-1 could cause a focal lesion by forcing transient but strong vasoconstriction in the circumscribed injected area. Its use in porcine stroke model has drawn attention lately. However, all the porcine endothelin-1 induced models were euthanized soon after surgery. Whether the brain lesion is persistent, and whether they could cause neurological deficit are not known...

Reversible cerebral vasoconstriction syndrome (RCVS) is a disease characterized by thunderclap headache with severe vasospasm of middle sized vessels of circle of Willis or the extracranial circulation which spontaneously revert back. We report a middle aged female with severe headache and vasospasm of the vertebral arteries and vessels of circle of Willis causing multiple cerebral infarcts. The vasospasm resolved within 3 months.

RNF213/Mysterin has been identified as a susceptibility gene for moyamoya disease, a cerebrovascular disease characterized by occlusive lesions in the circle of Willis. The p.R4810K (rs112735431) variant is a founder polymorphism that is strongly associated with moyamoya disease in East Asia. Many non-p.R4810K rare variants of RNF213 have been identified in white moyamoya disease patients, although the ethnic mutations have not been investigated in this population. In the present study, we screened for RNF213 variants in 19 Slovakian and Czech moyamoya disease patients...

Cerebral aneurysms are pathological focal evaginations of the arterial wall at and around the junctions of the circle of Willis. Their tenuous walls predispose aneurysms to leak or rupture leading to hemorrhagic strokes with high morbidity and mortality rates. The endovascular treatment of cerebral aneurysms currently includes the implantation of fine-mesh stents, called flow diverters, within the parent artery bearing the aneurysm. By mitigating flow velocities within the aneurysmal sac, the devices preferentially induce thrombus formation in the aneurysm within hours to days...

RATIONALE: Data from animal models of hypertension indicate that high blood pressure may develop as a vital mechanism to maintain adequate blood flow to the brain. We propose that congenital vascular abnormalities of the posterior cerebral circulation and cerebral hypoperfusion could partially explain the etiology of essential hypertension, which remains enigmatic in 95% of patients. OBJECTIVE: To evaluate the role of the cerebral circulation in the pathophysiology of hypertension...